Water-tube boiler.



Patented Ian. 9, |900.

G.v M. DAVIS. WAXTER TUBE BOILER.

(Application led Mar. 22, 1899.)

'KUHN l l l i l l 1 I l H l v Www/55555 Z //\/\/E/\/ TUR 607' NITED STATES PATENT OFFICE.

GEORGE M. DAVIS, OF HARTFORD, CONNECTICUT.

WATER-TUBE BOILER.

SPECIFICATION forming part of Letters Patent No. 640,879, dated January 9, 1900.

Application iiled March 22, 18499.

zen of the United States of America, and a resident of the cityand county of Hartford, in the State of Connecticut, have invented certain new and useful Improvements in Water- Tnbe Boilers, of which the following is a specification.-

This invention relates to boilers of that class generally known as upright water-tube boilers, one object of the invention being primarily to furnish an improved and si mplified boiler of this class embodying a furnace and to so construct and organize the parts thereof as to secure the maximum amount of heating-surface to the minimum amount of space occupied by the boiler as a whole; further, to so construct and dispose the fire-box and the water or steam tubes of the boiler as to facilitate a rapid generation of steam at an economic expense in fuel.

A further object of the invention is to furnish a boiler and furnace in which the boiler proper is constructed wholly of wrought-metal tubing and comprises a plurality of horizontally-disposed endless tubes, a multiplicity of vertical tubes disposed substantially concentric about a common center and communicating at their upper and lower ends with said endless tubes, a base supporting said vertical tubes and having an ash-pit, a grate supported within the circle described by the vertical tubes, and a so-called porcupine 1ocated within the circle of vertical tubes and having radially-disposed tubes communicating with said vertical tubes and endless tubes.

With these objects in view my invention consists in a boiler and furnace embodying certain novel features and improved details inconstruction and organization, as will be hereinafter fully described, and pointed out in the claims.

In the drawings accompanying and forming part of this specification, Figure l is a side elevation, partly in section, of a Watertube boiler and furnace embodyng my invention. Fig. 2 is a plan View, partly in section, of said boiler, the section being taken on a line corresponding with the dotted line 2 2, Fig. 1; and Fig. 3 is a detail on an enlarged scale, partly in elevation'and partly in central longitudinal section, of a portion of one Serial No. 710,072. (No model.)

end of a vertical ltube and the coupling by means of 'which said tube is connected to one of the horizontal .endless tubes of the boiler.

Similar characters designate like parts in all the figures of the drawings.

In the preferred construction and organization thereof illustrated in Figs. 1 and 2 of the accompanying drawings the boiler and furnace comprises, essentially, a base B, constructed, preferably, of cast metal in cylindrical form and having a suitable ash-pit 3; two concentrically and horizontally disposed cross-sectionally circular wrought-metal endless tubes located one above the other and designated, respectively,`by 4 and 5; an external series of vertical tubes 6, arranged side by side in close proximity, preferably in the arc of a circle about a common center and connected at opposite ends with the horizontal endless tubes 4 and 5 in such manner as to facilitate a circulation of water and steam through said vertical tubes and horizontal endless tubes; an internal porcupine set of tubes designated in a general way by P and embodying a central vertical tube 7, terminating in a steam-domeS and a series of radially and horizontally disposed branch tubes 9, some of which are closed at their outer ends andothers of which are connected for communication with the upper endless tube 5 and certain of the vertical tubes 6; an intermediate particircular horizontal tube 10, disposed a sufficient distance above the ringtube 4 as to form the upper part of the rebox Vopening l2, and which particircnlar tube 10 communicateswith the upper endless tube 'through the medium of certain of the vertical tubes 6, which are obviously made of reduced length as compared with others of said tubes 6; a lire-grate G, supported in any suitable manner Within the circle described by the external series of vertical tubes 6; an external casing 13 of suitable form surrounding the external series of tubes 6 and terminating at its upper end in a smoke-pipe 13'; a supply-pipe 14, communicating with the boiler near the base thereof, and a steampipe 15 in communication With the steamdome 8. All of the foregoing parts are shown in the drawings and will be hereinafter more fully described.

IOO

While the boiler illustrated in the accomside by side preferably in the arc of a circle and with their adjacent faces in such close proximity as to preclude the possibility of coal contained in the fire-box sifting through between said tubes.

As a convenient means of connecting the vertical tubes with the horizontal endless tubes said endless tubes are drilled and tapped, as will be understood by reference to the accompanying drawings, and the opposite ends of the vertical tubes 'are tapped to receive couplings C and C', the ones .C being screwed into the upper ends ot the vertical tubes 6 and the endless tube 5 and the ones C' being screwed into the lower end of the vertical tubes and the lower endless tube 4, as hereinafter more fully described.

For convenience in assembling and connecting up the vertical tubes and the .endless tubes I employ, preferably in connection with the lower ends of each vertical tube, an ordinary nipple-coupling C', one end of which is screwed into the lower end of the tube and the other end into the tapped opening in the lower endless tube Ll, said coupling or nipple having its screw-threaded ends preferably tapered to insure a water-tight joint, and I preferably employ, in connection with the upper end of each tube, an improved coupling C (see Fig. 3) of a construction which will enable each vertical tube to be readily connected up with the upper endless tube independent of the other vertical tubes,'which is of material advantage and saves much time in the setting up or assembling of the parts of the boiler. This coupling C comprises in the preferred from thereof (illustrated most clearly in Fig. 3) a substantially tubular main body portion 16, having one end, asA 17, thereof tapered externally and screwthreaded telit a correspondingscrew-threaded opening in the upper endless tube 5, and having the lower end 18 thereof straight and screw-threaded to lit a corresponding screwthreaded opening in the upper end of the vertical tube 6, the threads of the opposite ends of the main body portion of the coupling being, preferably, right-hand threads and being separated from each other by a polygonal or nut-like portion 19, adapted to be grasped by a wrench whereby to screw the coupling Y outward from the upper end of the tube 6 piece of packing 21, interposed between the upper end of the tube 6 and said jam-nut, whereby an impervious or steam-tight joint is provided.

In connecting up the upper end of the tube 6 with the upper horizontal endless tube 5 the coupling C will be screwed down far enough into the upper end of the tube 6 as to bring the upper end ot the coupling slightly below said endless tube, after which the coupling C will be screwed outward until the upper taperedscre w-threaded end thereof is screwed tightly into the tapered opening in said endless tube, which opening is concentric to said coupling, after which the jam-nut 2O will be screwed down until the packing 21 is tightly compressed between the same and the upper end of said tube.

The internally-disposed porcupine P, which is connected up in any suitable manner and communicates with the endless tubes and vertical tubes, may be of any desired construction and organization, it preferably vconsisting of the central tube before described, having a series of sets of radially and .horizontally disposed short branch tubes, said sets being located one above ,the other and communicating with the central tube at dilierent points inthe length thereof;

lIn practice, if desired, an asbestos packing (not shown) may be interposed between the outer series of vertical tubes 6 and the eX- ternal sheet-metal casing 13 to obviate accidental overheating of said casing.

In the drawings I have shown an ordinary simple form of grate; but it will be obvious that any suitable form of tire-box and grate may be employed, and, further, in practice the tire-box opening and ash-pit opening will be provided with suitable doors, which for convenience are not shown in the accompanylug drawings.

By arranging the vertical tubes in close proximity to each other and connecting them up with the endless tubes, as described, and as illustrated in the accompanying drawings, and providing a porcupine set'of tubes and connecting this up with the ring-tubes and vertical tubes I secure a greater amount of effective heating-surface than has been heretofore possible in boilers of this class of the same size and at the same time produce a boiler in which steam may be quickly generated at a minimum expense in fuel, and which will withstand extreme high pressure, for the reason that all of the tubes of said boiler will, in practice, be constructed of wrought-steel.

I claim- 1. A boiler and furnace comprising a base; a horizontally-disposed wrought-metal end less tube supported on said base and having a water-supply pipe in communication therewith a multiplicity of vertically-disposed wrought-metal tubes disposed in the arc of a circle abouta common center; a horizontallydisposed endless tube supported above and in concentric relation with the lower endless IIO tube; a series of hollow couplings adjustably connecting the upper and lower ends of the vertical tubes to the upper and lower endless tubes respectively; a steam-dome vertically disposed within th'e circle described by the vertical tubes; a multiplicity of radially and horizontally disposed tubes comm unicating with the steam-dome and vertical tubes; a steam-pipe communicating with the steamdome; and a grate supported within the circle described by the vertical tubes.'

2. A boiler and furnace comprising a base; a horizontally-disposed wrought-metal endless tube supported on said base and having a series of tapered screw-threaded'openngs in the upper wall thereof; a superposed endle'ss tube having a series of tapered screwthreaded openings in the lower wall thereof, amultiplicity of concentrically-disposed crosssectionally circular vertical wrought-metal tubes interposed between the upper and lower horizontal tubes and having screw-threaded openings in the upper and lower ends thereof to receive couplings; hollow couplings screwed into the upper and lower ends of said vertical tubes and having tapered externallyscrew-threaded outer ends iitting the tapered screw-threaded openings in the upper and lower horizontal tubes respectively; a grate supported within the circle described by the vertical tubes; a casing surrounding the Vertical and horizontal tubes; asteam-dome vertically disposed in the center of the arc described by the vertical tubes; a multiplicity of radially-disposed tubes communicating with the steam-dome and vertical tubes; a water-supply pipe communicating with the lower endless tube; a steam-pipe communicating with the steam-dome and a grate supported within the circle described by the vertical tubes. l

Signed by me at Hartford, Connecticut, this 20th day of March, A. D. 1899.

GEORGE M. DAVIS. 

